So, it's really hard to compare the Steam Controller to a traditional controller because it's SO DAMN NON-TRADITIONAL.
I mean, you've got a joystick on your left and your A,B,X,Y's on your right, analog triggers and click bumpers on the back, but in addition, you've got 2 grip buttons and those oh so unique circle pads.
So how does it stack up against a DS4 in regards to performance? It's got great battery life (80 hours advertised, haven't owned it long enough to kill it, but I've used it everyday since getting it so we'll see), great wireless range, (i can use my PC with it from my kitchen, PC in bedroom down the hall) and the input latency is excellent.
That said, here's where the Steam Controller sets itself apart from the DS4 and why it was created to begin with.
You kick ass with a DS4 on PC. I used an Xbox 360 controller on PC. And brother, in shooters I SUCK with a traditional controller. I can't do my twitchy impulse aiming with a joystick, I just can't get that control that I get with the reflex of a mouse in my hand you know?
With the Steam Controller, I can get that. With some training (in about 2 days, I think I'm beginning to match myself in skill with the mouse and keyboard) I'm able to surpass my skill with a traditional controller.
Will you be able to get a better experience with the Steam Controller as opposed to the DS4? It depends on what you're accustomed too. If you like the ability to swing around and head shot someone with the pin point accuracy of a mouse, and FAST, then you may prefer the Steam Controller. But it WILL TAKE PRACTICE. I can't repeat that enough, sorry.
But if you like the smooth movements and control you get with a joystick and that's more comfortable, then this would take some getting used to.
You asked about the Haptic Feedback. This is one of the reasons I bought this thing, there's no other product that uses this kind of tech to my knowledge and I'm a sucker for gimmicks like this.
But as an example, and it's hard to explain but I'll try, say you set the pad to Trackball mode. You run your thumb across it, and a tiny speaker inside the pad literally shoots "clicks" of sound into your fingertip, so that you're feeling the artificial tactile feedback that feels like you're really rolling a trackball. You swipe your thumb, and you feel the clicks of sound simulate the faded slowing of the trackball because you released your finger. The cursor on your screen slows to a stop because the "trackball" stopped rolling.
Then you could set the pad to joystick mode, where the haptic feedback will simulate the resistance of a joystick under your thumb with those same sound waves. The smooth movement of the joystick appears on your screen. This mode, isn't my favorite though, because I'm so used to the twitchiness of the mouse.
In straight mouse mode though, it's just like the circle pad is the touchpad on a laptop, the haptic feedback does it's thing here too, sending soundwaves into your fingertip, simulating the resistance of the trackpad.
As I said in my op as well, this controller is the king of optimization and customization, make any button do anything. Make your controller half keyboard and mouse, half traditional controller. Turbo modes, sensitivity adjustments, you name it.
Plus, when not in a game, it doubles as a regular PC mouse, I can right click, left click, scroll click, directional button all around my computer. I don't even use my mouse anymore. I don't think the DS4 can do this can it? Without special software right?
Anyways, SORRY for the mouthful. I tried!